Fatty acids for use as a medicament

ABSTRACT

The invention relates to fatty acid stimulation of rectal mucosa initiating the process of defecation, acting as a laxative. Furthermore, the invention relates to the usage of free fatty acids, fatty acid mixtures and fatty acid extracts from marine lipids in pharmaceutical formulations such as suppositories, ointments, tablets and gelatin capsules for treatment and prevention of multiple disorders like constipation, hemorrhoids, bacterial infections (e.g.  helicobacter pylori ), viral infections (e.g. herpes simplex virus infections) and inflammations, as well as against fissura ani and pruritus ani.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of prior U.S. applicationSer. No. 12/609,845 filed Oct. 30, 2009, which claims the benefit ofU.S. Provisional Application No. 61/110,093 filed Oct. 31, 2008, andU.S. Provisional Application No. 61/174,144 filed Apr. 30, 2009, theentire content of each is hereby incorporated by reference herein.

TECHNICAL BACKGROUND AND PRIOR ART

Laxatives are used to treat constipation, i.e. the absence of regulardefecation, accumulation of feces in the colon and/or the passage ofsmall amounts of hard, dry stools. People who are constipated may findit difficult and painful to have a bowel movement. Laxatives are alsoused to cleanse the lower bowel before a proctoscopy, rectoscopy,colonoscopy, x-ray imaging of the colon or similar diagnostic procedure.There are several types of laxatives, see overview in Table 1. Laxativescan produce side effects, but usually not serious ones. Stimulants andirritants are more likely than other types of laxatives to cause sideeffects such as abdominal discomfort, faintness and cramps. Laxativesmay be for oral administration, e.g. tablets, capsules and liquids, orfor rectal administration, e.g. suppositories and enemas. Orallyadministered laxatives can reduce bioavailability of drugs andnutrients.

Castor oil is a well known laxative, a usual therapeutic adult dose forlaxative effect is 15 to 60 mL, administered orally. About 90% of thefatty acid content in castor oil is the triglyceride formed fromricinoleic acid (12-hydroxy-9-cis-octadecenoic acid), a monounsaturatedfatty acid, which is the active component of castor oil, acts as alaxative by stimulating secretion of fluid and electrolytes in the smallintestines. One or two copious of semi-fluid stools are released within2 to 6 hours of the administration. Ricinoleic acid is effective inpreventing the growth of numerous species of viruses, bacteria, yeastsand molds, and it does possess some anti-inflammatory effect (Vieira etal. 2000; Burdock et al. 2006). Short chain fatty acids, such as lactic,acetic, butyric and propionic acid, can stimulate colonic motility andby increasing the osmotic pressure (i.e. hyperosmotic agents, Table 1).

Lubiprostone(difluoropentyl-2-hydroxy-6-oxooctahydrocyclopenta-heptanoic acid) is abicyclic fatty acid derived from a metabolite of prostaglandin E1. Afteroral administration lubiprostone activates specific chloride channels(ClC-2 channels) in the gastro-intestinal tract to stimulate intestinalfluid secretion, increase GI transit, and improve symptoms ofconstipation (B. E. Lacy 2008). Thus, lubiprostone has a receptorspecific effect.

TABLE 1 Types of laxatives Class Site of action Onset of actionMechanism of action Examples Bulk-producing Small and 12-72 hoursIncrease the volume of the Psyllium, agents large intestine stool(retain more water), methylcellulose, and will both soften the dietaryfibers stool and stimulate intestinal motility. Stool Small and 12-72hours Hold water and fats within Docusate (a softeners and largeintestine the stool, making it easier surfactant) surfactants to movealong. Saline Small and 0.5-6 hours Retain water in the Magnesium largeintestine intestinal lumen, increasing hydroxide, intraluminal pressuremagnesium sulfate, leading to softer stool. sodium phosphate Lubricantsand Colon 6-8 hours Make the stool slippery so Mineral oil emollientsthat it slides through the intestine more easily. Retards absorption ofwater. Hyperosmotic Colon 0.5-3 hours Act by the osmotic effectSorbitol, lactulose, agents that retains water within the polyethyleneintestine glycol, glycerin suppositories Stimulants Colon 6-10 hoursStimulate peristaltic action, Bisacodyl tablets, and irritants i.e.contraction of smooth senna Colon 6-8 hours muscles that propelPhenolphthalein Small intestine 2-6 hours contents through the Castoroil Colon 0.25-1 hour digestive tract. Bisacodyl suppositories FoodsFigs, olive oil, prunes

It has been documented that saturated and unsaturated fatty acidspossess both antibacterial and antiviral activity, and that the fattyacids play a role in the natural defense against infections in mucosalmembranes and skin, see e.g. Kabara (1978). In vitro studies have shownthat free fatty acids kill enveloped viruses, such as Herpes simples-1and Herpes simplex-2, Gram-positive bacteria, Gram-negative bacteria,such as Helicobacter pylori, and fungi (see Khulushi et al. (1995),Thormar et al. (2007), Carballeira (2008)).

The dietary and nutritional benefits of essential fatty acids are wellknown and dietary supplements such as fish oils have been used for along time, providing poly-unsaturated fatty acids (PUFAs), also referredto as highly-unsaturated fatty acids (HUFAs), in the form oftriacylglycerides (TAGs) also called triglycerides. The so calledessential omega-3 fatty acids are particularly beneficial.

EP 420056 discusses that fat base suppositories, in particular thosebased on non-lauric cocoa butter substitute, can cause irritation whichis induce by the fat base. The document suggests to add to thesuppositories fatty acids, fatty acid salts or fatty acid esters toreduce the irritation caused by the fat base.

New laxatives with little side effects and discomfort would be muchappreciated.

SUMMARY OF INVENTION

The invention is based on the surprising discovery that fatty acids havea clear and significant laxative effect and can be beneficially used toinitiate defecation in subjects suffering from constipation and/or hardstools or where cleansing of the rectum and lower bowel. Examplesprovided herein demonstrate a clear and convincing effect of fatty acidsin this regard. Pharmaceutical dosage forms are provided and medicalmethods based on these findings.

The gastrointestinal tract wall (rectal mucosa) contains polymodalnociceptors which are activated by a variety of mechanical, chemical, orosmotic stimuli and send via primary afferent neurons information to theenteric nervous system (intrinsic innervation) and to the CNS viasympathetic and parasympathetic pathways (extrinsic innervations). Theinventors have discovered that free fatty acids and fatty acid mixturesact as chemical bowel stimulant on the polymodal nociceptors in therectal mucosa initiating the process of defecation.

Pharmaceutical dosage forms for other medical conditions are alsopresented, based on the anti-inflammatory, antiviral and antibacterialeffects of the fatty acids. Provided herein are dosage forms fortreatment of diseases and conditions including hemorrhoids, fissura aniand pruritus ani. New and useful compositions of fatty acids aredisclosed, including compositions with fatty acids and cyclodextrins,which are shown to be stable and effective.

Haemorrhoids, anal fissure and pruritus ani are all common benign analdiseases that conventionally rely on corticosteroid based medication fortheir treatment. The present invention substitutes steroid-containingdrugs with non-steroid products derived from natural sources such asfish oil, in addition to the use of these products as laxatives.

DETAILED DESCRIPTION

The invention provides in a first aspect a pharmaceutical dosage formfor administration to rectum and/or the large intestine for the purposeof inducing defecation (bowel movements), i.e. inducing and/orstimulating the process. The dosage form comprises as an activeingredient one or more fatty acid. The one or more fatty acid issuitably in a form selected from free fatty acid, salt of fatty acidwith a pharmaceutically acceptable counter ion, fatty acid ethyl esterand fatty acid monoglyceride. Free fatty acids are the presentlypreferred embodiment.

The one or more fatty acid preferably has a chain length in the range offour to 36 carbon atoms, such as a chain length in the range of 4 to 24and more preferably a chain length in the range of 8 to 24 carbons. Morepreferably the one or more fatty acid comprise a mixture of fatty acids,which can be derived from suitable natural lipid material such as oilsof animal or vegetative origin, fractions thereof or a mixture thereof.

Fatty acids useful in the invention include saturated fatty acids suchas hexanoic acid (caproic acid) (6:0), heptanoic acid (enanthic acid)(7:0), octanoic acid (caprylic acid) (8:0), nonanoic acid (pelargonicacid) (9:0), capric acid (10:0), undecylenic acid (11:0), lauric acid(12:0), tridecylic acid (13:0), myristic acid (14:0) palmitic acid(16:0), and stearic acid (18:0). Unsatured fatty acids which are usefulinclude palmitoleic acid (16:1 n-7), oleic acid (18:1 n-9), elaidic acid(18:1), linoleic acid (18:2 n-6), linolenic acid (18:3), arachidonicacid (20:4 n-6), gadoleic acid (20:1 n-11), gondoic acid (20:1 n-9;cis-11 eicosenoic acid), erucic acid (22:1 n-9) and cetoleic acid (22:1n-11).

Useful vegetable oils as raw material for the fatty acids of theinvention include safflower oil, corn oil, almond oil, sesame oil,soybean oil, linseed oil, rapeseed oil, grape seed oil, sunflower oil,wheat germ oil, hemp oil, and any mixtures thereof.

In preferred embodiments the fatty acids are derived from oil materialwhich is pharmaceutically acceptable and defined according toPharmacopoeia standards (pharmaceutical grade oils). Such oils includemarine omega oils such as Omega-3 Fish Oil (Lysi, Iceland).

In a preferred embodiment the one or more fatty acids comprise a mixtureof fatty acids comprising at least about 20 wt % of unsaturated fattyacids and at least about 5 wt % polyunsaturated fatty acids. The termpoly-unsaturated fatty acid indicates a fatty acid with more than onedouble bond in its acyl sidechain and is used herein interchangeablewith the term highly-unsaturated fatty acid or HUFA. Many natural oilsprovide such fatty acid composition, e.g. the vegetable oils mentionedabove, and fish oils and other marine oils as well, which provide a highfraction of PUFA. Among poly-unsaturated fatty acids useful in theinvention are the omega-3 fatty acids alpha-linolenic acid (18:3),stearidonic acid (18:3), moroctic acid (18:4 n-3), eicosatrienoic acid(20:3), eicosatetraenoic acid (20:4), eicosapentaenoic acid (20:5; EPA),docosapentaenoic acid (22:5), docosapentaenoic acid (22:5), anddocosahexaenoic acid (22:6; DHA), tetracosapentaenoic acid (24:5), andtetracosahexaenoic acid (24:6). Other useful polyunsaturated fatty acidsare omega-6 fatty acids including linoleic acid (18:2 n-6),gamma-linolenic acid (18:3 n-6), eicosadienoic acid (20:2). Thedesignation in parantheses indicates the total number of carbon atoms inthe acyl chain and the number of double bonds, thus 18:3 is a fatty acidwith 18 carbon atoms and three double bonds. The omega number indicateshow far from the lipophilic end of the acyl chain the first double bondis situated, also indicated with n, as is used for other unsaturatedfatty acids above.

In a useful embodiment, the pharmaceutical dosage form comprises amixture of fatty acids derived from marine organisms. Marine organismsuseful as sources of the fatty acid material include marine animal oilderived from an animal source selected from fish liver oil including codliver oil, tuna oil; fish flesh or fish meal including flesh or mealfrom herring, capelin, mackerel, menhaden, sardine, anchovy, horsemackerel, blue whiting, and tuna; planktonic organisms, squid andmolluscs.

Oils such as the above mentioned are readily converted to free fattyacids by hrolysis

As mentioned above, the pharmaceutical dosage form of the invention forlaxative action is suitably formulated for administration to rectumand/or lower intestines. Consequently, any type of dosage form suitablefor administration at said site is within the scope of the presentinvention. Currently contamplated dosage forms include suppositories,ointment, cream, lotion, paste, gel, and formulations for enemadelivery. Suppositories are well known in the art, they are generallyformulated to be solid at room temperature and up to at least about 30°C. but having a melting temperature below the normal human bodytemperature of 37° C. It is therefore common to formulate suppositorieswith a fat base, such as cocoa butter, which fulfils the above meltingpoint criteria. Cocoa butter is a mixture of triglycerides of saturatedand unsaturated fatty acids which can be manipulated in solid form atroom temperature but melts completely at body temperature. More recentmaterials include so called cocoa butter substitutes (CBS), whichinclude the following categories: interesterified fully hydrogenatedpalm kernel oil, fully hydrogenated palm kernel stearine, mid fractionsof hydrogenated vegetable oils which are rich in trans-fatty acids andsemi-synthetic glycerides.

Useful commercially available fat bases suitable for the presentinvention include Suppocire™ (Gattefosse) lipophilic bases, asemi-synthetic vegetable based oil base available in several gradesincluding Suppocire™ AS, AS2X, NA, Novata™ (Henkel Int.) includingNovata A, Novata B, and Novata BC, Witepsol™ (Dynamit Nobel Ab) such asWitepsol™ H5, H12, H15, H32, H35, W25, W31, W32, W32, W35, and W45;Massa Estarinum™ (SASOL), incl. Massa Estarinum™ of the grades B, BC, Eand 299.

The suppositories of the present invention may suitably comprise any ofthe above mentioned materials as base. Hydrophilic waxes can also beused in the invention, such as the polyethylene glycols (eg PEG 1500,PEG 3000, PEG 4000 and mixtures thereof). Suppocire AP, is anamphiphilic base comprising saturated polyglycolysed glycerides.

Further base components may suitably be added, such as beeswax, carnubawax or the like.

Th suppository dosage form may also in some embodiments comprise furtherexcipients such as but not limited to binders and adhesives, lubricants,disintegrants, colorants and bulking agents.

Suppository dosage forms of the invention will generally comprise in therange of 50-2000 mg of the fatty acid active ingredient, and preferablyin the range of 50-1000 mg, such as in the range of 100-750 mg,including about 100 mg, about 200 mg, about 300 mg, about 400 mg orabout 500 mg. Smaller suppositories for pediatric use are also withinthe scope of the invention, which generally would be smaller andcomprising in the range of 50-750 mg fatty acid active agent, such as inthe range of 50-500, e.g. about 50 mg, about 75 mg, about 100 mg, about200 mg, about 300 mg or about 400 mg. Depending on the desired dose andthe desired total size of the suppository the amount of fatty acidactive ingredient may comprise in the range of about 5 wt % to about 75wt % of the total weight of the dosage form, such as in the range ofabout 5-50 wt %, including in the range of about 10-50 wt %, such as inthe range of about 10-40 wt %.

A common size of molded or kneaded suppositories for adult use accordingto the invention is in the range of about 2-3 mL, such as about 2.0 mL,about 2.2 mL or about 2.5 mL. Depending on the excipient composition,this would generally correspond to a weight in the range of about 1.5 toabout 3 g, accordingly, the suppositories according to the invention aresuitably in said weight range, such as about 1.8 g, about 2.0 g, about2.2 g or about 2.5 g.

A suitable size for pediatric suppositories would generally be abouthalf the above size, such as in the range of 0.5-1.5 mL, e.g. about 0.5mL, about 0.8 mL, about 1.0 mL, about 1.2 or about 1.5 mL.

It has been found useful to include in the suppository dosage form ofthe invention an excipient oil component such as a triacylglyceride oil(the term triacylglyceride oil indicating herein a natural, synthetic ormixed oil which comprises dominantly triglycerides, such as any of theabove mentioned oils, but may also include some fraction ofdiacylglycerides and monoacylglycerides), to reduce discomfort duringaction of the medicament and bowel movements. Accordingly, the dosageform of the invention preferably comprises in the range of about 5-50 wt% triacylglyceride oil, including the range of about 5-35 wt %triacylglyceride oil, such as more preferably in the range of about 5-25wt %, such as about 5 wt %, about 10 wt %, about 15 wt % or about 20 wt%. The base is in these embodiments composed accordingly in order tohave a desired melting point of the overall composition of the dosageform. Preferably the triacylglyceride oil is a pharmaceutical gradeoil,such as fish oil derived Omega oil as mentioned above, or anyothersuitable well defined pharmaceuticall acceptable oil.

It is useful to include anti-oxidants in the dosage forms of theinvention, such as but not limited to butylated hydroxyanisole (BHA),butylated hydroxytoluene (BHT), ascorbic acid or a salt thereof, asulfatide salt, citric acid, propyl gallate, alfa-tocopherol, andascorbyl palmitate. Depending on the selected antioxidant compound, asuitable amount is e.g. in the range of about 0.05-0.5 wt %, such as inthe range of 0.1-0.3 wt %. Further preservative agents may included insome embodiments, such as any of those of the group consisting ofbenzoic acid or derivatives thereof, including ofC₁₋₆-alkyl-p-hydroxy-benzoic acids, such as methyl-p-hydroxy-benzoicacid, ethyl-p-hydroxy-benzoic acid, propyl-p-hydroxy-benzoic acid,butyl-p-hydroxy-benzoic acid, and mixtures thereof. In a particularinteresting embodiment, the preservative is a mixture ofmethyl-p-hydroxy-benzoic acid and propyl-p-hydroxy-benzoic acid, in theproportion of from about 3:1 to about 5:1 by weight, preferably in theproportion of about 4:1 by weight.

The preservative or preservatives is/are preferably present in theformulation in such a concentration of about 0.05-0.2% by weightcalculated on the formulation, that it does not to any substantialextent impair the activity of the lipid or lipids.

The suppository dosage form of the invention are preferably provided inisolating packaging to further inhibit air oxidation, such as alu-alublister packaging, Duma containers or the like.

Enema formulations are generally liquid or semi-liquid formulations tobe administered with suitable pharmaceutical grade enema rectalapplicator. Preferred applicators are those that deliver the suitabledose of the formulation by breaking open a sealed dosage form container,such as e.g. described in U.S. Pat. No. 4,657,900.

In another aspect, the invention provides a method for stimulatingand/or initiating the process of defecation, which comprisesadministering to the rectum and/or lower intestines one or more fattyacids. The method is based on the stimulating effect of the fatty acidson the polymodal nocireceptors in the rectal mucosa. The fatty acid ispreferably selected from any of the above mentioned fatty acids andmixtures of fatty acids and can formulated in a suitable form such as inany of the forms described above.

As can be understood from the above discussion, free fatty acids are thepreferred form of fatty acids in the method, although other forms arecontemplated, such as fatty acid ethyl esters, salt of fatty acids andfatty acid monoglycerides.

The method will generally comprise administering in the range of about100 to 2000 mg fatty acids, such as in the range of 100-1000 mg, or anyof the above mentioned ranges and amounts.

In the presently preferred embodiment, the method comprisesadministration of the active ingredient to the rectum and/or lowerintestines. Accordingly, the method preferably comprises administeringdosage forms as described above, including suppositories, enemas orother formulation types introduced through the anus.

A further aspect of the invention provides fatty acid for use as amedicament for stimulating and inducing the process of defecation. Theexamples provided herein demonstrate a clear clinical effect of thefatty acids acting as active ingredient for the stated medicalindication and clinical action. As illustrated in Example 6, the effectis attributed to fatty acids but not triacylglyceride oil used asexcipient. The fatty acid of the invention is preferably in the form offree fatty acid or any of the other defined forms above and preferablythe fatty acid is provided as a mixture of fatty acids. Suitably andpractical mixtures can be obtained from natural sources, derived fromanimal or vegetative oils or mixture thereof, as those mentioned above.

In the below Example 1 is described how a preferred extract of freefatty acids is produced by acid hydrolysis of a marine fish oil.Accordingly, a fatty acid mixture obtainable from hydrolysis of naturaloil, such as from a vegetable oil or fish oil, for use as a laxativemedicament is included in the invention. The fatty acid of the inventionis preferably formulated in a dosage form of the invention, such as inparticular as a suppository, preferably as further described herein.

Fatty acids for use in the invention can be suitably provided byhydrolysis of natural oils such as those above mentioned. Hydrolysis oftriglycerides can be acid or base catalysed. As illustrated in theaccompanying Examples, acid hydrolysis of a natural oil such as fish oilyields useful fatty acids, the composition of the resultant fatty acidmixture is substantially similar to the fatty acid composition of theoil raw material and will vary depending on the natural source and anydesired composition can be derived by mixing different sources, eithermixing natural oils prior to hydrolysis or mixing individual fatty acidsor fatty acid mixtures. The fatty acid composition of different fishspecies and fish oil is well documented and known to the skilled person.

Ethyl esters of fatty acids for use in the invention can be obtained byesterification of free fatty acids such as with a suitable lipase, suchas but not limited to lipase from Rhizomucor miehei (MML), Pseudomonassp. lipase (PSL) and Psedomonas fluorescens lipase (PFL). See e.g.Halldorsson et al (2004), WO 95/24459, WO 00/49117 and U.S. Pat. No.7,491,522.

Monoglycerides can be obtained by selective esterification with glycerolwith lipase under suitable reaction conditions, for an overview see,Osman et al. (2006).

A further aspect of the invention provides pharmaceutical formulationsand dosage forms with fatty acids and cyclodextrins. Cyclodextrins arecyclic oligosaccharides and are ueful for forming host-guest complexeswith hydrophonic molecules. The inventors have found that dry fatty acidpowders can be readily provided in combination with cyclodextrins.Cyclodextrin compounds that are useful in the invention includealfa-ayclodextrin, beta-cyclodextrin and gamma-cyclodextrin and theirderivatives, such as 2-hydroxypropyl-alfa-cyclodextrin,2-hydroxypropyl-gamma-cyclodextrin and sulfobutylethergamma-cyclodextrin. Useful dry fatty acid powders can comprise about 1:1ratio of fatty acids and cyclodextrins, or in the range of from 1:2 to2:1 fatty acids to cyclodextrins, e.g. a ratio of about 2:1 (67:33)fatty acids:cyclodextrin, or a ration of about 3:2, or about 1:1, orabout 2:3, or 2:1. Cyclodextrin-fatty acid compositions according to theinvention were found to be substantially more stable than the fattyacids.

The dosage form is in some embodiments a dosage form for oraladministration, such as a tablet, sachet or capsule. Such dosage formscan be formulated by conventional methods with the fattyacid-cyclodextrin complex converted to dry form as described herein.

Tablets are a preferred embodiment, they can be readily formulated bye.g. direct compression, dry granulation (slugging or roller compaction)or wet granulation. direct compression is preferred for this invention.Dry granulation consists of blending, slugging the ingredients, dryscreening, lubrication, and compression. The wet granulation method isused to convert a powder mixture into granules having suitable flow andcohesive properties for tableting. The procedure includes mixing the dryingredients in a suitable blender followed by adding a granulatingsolution under shear to the mixed powders to obtain a granulation. Thedamp mass is screened through a suitable screen and dried by tray dryingor fluidized bed drying. Alternatively, the wet mass may be dried andpassed through a mill. The overall process includes: weighing, drypowder blending, wet granulating, drying, milling, blending lubricationand compression. Direct compression is a relatively quick process wherethe powdered materials are compressed directly without changing thephysical and chemical properties of the drug. The fatty acid compound,direct compression excipients and any other auxiliary substances, suchas a glidant and lubricant are blended, e.g. in a twin shell blender orsimilar low shear apparatus before being compressed into tablets.

Excipients which may be present include one or more of diluents,binders, disintegrants, lubricants, glidants and colorants. A glidantmay be added to improve the flow of powder blend in the hopper and intothe tablet die. Lubricants are typically added to prevent the tabletingmaterials from sticking to punches, minimize friction during tabletcompression, and allow for removal of the compressed tablet from thedie. Lubricants are commonly included in the final tablet mix in amountsusually less than 1% by weight. Lubricants which can be used in theinvention include but are not limited to magnesium stearate, stearicacid, hydrogenated oil, and sodium stearyl fumarate.

Tablets of the invention can further comprise one or more diluent, addedto increase the bulk weight of the blend resulting in a practical sizefor compression and/or affect the properties of the blend forcompression. Typical diluents which can be used include for exampledicalcium phosphate, calcium sulphate, lactose, dextrates, dextrins,cellulose (preferably microcrystalline cellulose), mannitol, sodiumchloride, dry starch, pregelatinized starch and other sugars. Bindersare used to impart cohesive qualities to the powdered material. Usefulbinders include starch, gelatin, sugars such as sucrose, glucose,fructose, mannitol, sorbitol, dextrose, and lactose, natural andsynthetic gums, carboxymethylcellulose, methylcellulose,polyvinylpyrrolidone, ethylcellulose and waxes. A disintegrant may beincorporated to ensure that the tablet has an acceptable rate ofdisintegration. Typical disintegrants include starch derivatives,crospovidone, croscaramelose and salts of carboxymethylcellulose. Somebinders, such as starch and cellulose, are also excellent disintegrants.

Another useful dosage form of the invention is a capsule. Suitablecapsules of appropriate size for a given dosage size are well known tothe skilled person and include but are not limited to hard gelatinecapsules, soft gelatine and are more preferably hydroxypropylmethylcellulose capsules.

In the dosage form of the invention, the amount of active ingredient canbe relatively large, such as in the range of about 50-2000 mg fattyacids, including the range of about 100-2000 mg, such as in the range ofabout 100-1000 mg, such as about 200-1000 mg, including about 200 mg,about 250 mg, about 300 mg, about 500 mg, about 750 mg or about 1000 mg.Consequently, it is preferred that the total amount of excipients in atablet or capsule of the invention does not add too much mass to thedosage form. Accordingly, it is preferred that excipients comprise lessthan about 25 wt %, such as less than about 20 wt % and more preferablyless than about 15 wt %.

Further useful embodiments include dosage forms for topicaladministration such as but not limited to an oinment, cream, lotion,gel, emulsion, liposomes, or paste. These dosage forms are suitablyformulated with conventional ingredients and excipients. gels, such asfor iontopophoresis, suspensions and emulsions, including oil/water(w/o), w/o, o/w/o, w/o/w emulsions or microemulsions. These dosage formsare suitably provided by mixing a dry powder of fatty acid-cyclodextrincomplex with suitable ingredients, in a hydrophobic or hydrophilicbasis. The basis may comprise hydrocarbons such as hard, soft or liquidparaffin, glycerol, waxes (e.g., beeswax, carnauba wax), metallic soap,a mucilage, an oil of natural origin such as corn, almond, castor, orolive oil, mineral oils, animal ols (perhydroxysqualene); or a fattyacid such as stearic or oleic together with an alcohol such as ethanol,isopropanol, and propylene glycol. The formulation may include anysuitable surface active agent such as an anionic, cationic, or non-ionicsurfactant such as sorbitan esters or polyoxyethylene derivativesthereof. Suspending agents such as natural gums, cellulose derivativesor inorganic materials such as silicaceous silicas may also be included.The formulations may additionally comprise absorbtion promoters,stabilizers, e.g. protein stabilizing agents, known in the art.

The topical dosage forms preferably include an antioxidant such as anyof those mentioned above for oral dosage forms.

EXAMPLES Example 1 Preparation of Fatty Acid Extract

Preparation of the fatty acid mixture from fish oil: The fatty acidmixture is extracted from fish oil (such as fish-liver oil, for examplecod-liver oil) after hydrolysis in aqueous media. Sodium hydroxide (130grams) is dissolved in a mixture of 1.0 liter of ethanol and 1.5 literof purified water. Then 1000 grams of cod-liver oil is added and themixture heated under reflux at 85° C. for 8 hours. Then after cooling to5° C. 800 ml of 6M hydrochloric acid is added and the oil phaseseparated from the aqueous solution. The oil is then washed four timeswith 800 ml of purified water at 50° C. and finally dried at roomtemperature under vacuum. The fatty acid composition of the extract andthe cod-liver oil used to prepare the extract is determined bygas-chromatography. The relative fatty acid composition of the extractis approximately the same as in the unhydrolyzed oil (Table 4).

TABLE 2 The fatty acid composition of triglycerides found in cod-liveroil and its fatty acid extract. Composition (%) Fatty acid Cod-liverFatty acid Name Number oil extract Myristic acid 14:0 3.4 3.8 Palmiticacid 16:0 10.2 11.4 Palmitoleic acid 16:1 n-7 6.6 7.0 Stearic acid 18:02.3 2.5 cis-Vaccenic acid 18:1 n-7 4.4 4.4 Oleic acid 18:1 n-9* 17.618.8 Linoleic acid 18:2 n-6 1.2 1.3 Moroctique acid 18:4 n-3 2.1 2.1cis-11-Eicosenoic acid 20:1 n-7 0.4 0.5 Gondoic acid 20:1 n-9 9.6 9.4Gadoleic acid 20:1 n-11 1.9 2.1 Eicosapentaenoic acid 20:5 n-3 8.3 7.5Erucic acid 22:1 n-9 0.6 0.6 Cetoleic acid 22:1 n-11 9.0 9.7 Clupandonicacid 22:5 n-3 1.4 1.4 Docosahexaenoic acid 22:6 n-3 11.1 9.7 *includeslinolenic acid (18:3 n-3) that was not separated from 18:1 n-9 in the GCsystem. Cod-liver oil usually contains less than 1% linolenic acid.

Example 2 Suppositories with Fatty Acid Extract

Suppositories were prepared by the fusion method. White beeswax (ApifilGattefosse, France; 50 grams), glycerol dibehenate (Compritol 888,Gattefosse; 19 grams) and hard fat (Suppocire NA 0, Gattefosse; 530grams) were melted and mixed at about 75° C. and allowed to cool to 50°C. Then tocopherol antioxidant mixture (Coviox T70, Cognis, Germany; 1gram), cod-liver oil (100 grams) and the fatty acid extract (300 grams)were added and after thorough mixing and cooling to 45° C. the mixturewas poured into a suppository mold (2.2 ml) and cooled at roomtemperature. Suppositories containing 10% and 20% fatty acid extract, aswell as suppositories containing either cod-liver oil (100 grams) orfatty acid extract (300 grams), where additional amounts of Suppocire NA0 replaced the other ingredient, were prepared by the same method.

TABLE 3 Ingredient Amount in batch Relative amount Beeswax (Apifil)  50g   5% glycerol dibehenate  19 g 1,9% (Compritol 888) hard fat(Suppocire NA 0)  530 g  53% Tocopherol (Coviox T70)   1 g 0,1%cod-liver oil  100 g  10% fatty acid extract  300 g  30% Total 1000 g

Example 3 Ointment with Fatty Acid Extract

Ointments were prepared by the fusion method. Beeswax (Apifil,Gattefosse; 49 grams), glyceryl distearate (Precirol ATO, Gattefosse; 20grams) and petrolatum (white soft paraffin Ph.Eur; 330 grams) weremelted together over water bath at 65 to 75° C. After cooling to 50° C.cod-liver oil (300 grams), fatty acid extract (300 grams) and tocopherolantioxidant mixture (Coviox T70, Cognis; 1 gram) were added to thisbase. Then, after cooling to room temperature, the ointment was filledinto 30 ml aluminum tubes.

Example 4 Double-Blind Study with Suppositories

A double-blind study was conducted with 30 healthy volunteers. On day 1the participants underwent an anal examination and randomized into studygroup, receiving the active ingredients (suppositories and ointmentscontaining 30% omega enriched fatty acid mixture, see Table 2 andExamples 2 and 3), and control group, receiving placebo (identicalsuppositories and ointments without fish-liver oil and the fatty acidmixture) for a total study period of two weeks. The study groupconsisted of 3 males and 12 females, with the mean age of 46 years. Thecontrol group consisted of 6 males and 9 females with the mean age of 43years. The participants administered the suppositories in the rectum andapplied the ointment to the perianal area twice a day with clinicalexamination after the first week with anal examination where any sign oferythema, inflammation, blood or sores were recorded. After the secondweek the volunteers underwent final examination. The participants alsoanswered a questionnaire about the effect of the suppositories on theirbowel movement during control examination after week one and two.

The anal examination conducted after week one and at the final controldid not reveal any toxic skin reactions in either group. There was nostatistically significant difference regarding complaints of itching ormild pain between the groups. In the study group 93% felt the urge fordefecation and passed stools, most within 10 minutes afteradministration of suppositories. In the control group only 37% felt theurge for defecation after administration of suppositories. Thedifference was statistically significant (P=0,000). The suppositoriesclearly stimulated bowel movement causing defecation without causingdiarrhea, mucosa secretion or any prolonged effect after defecation.

Example 5 Comparison—Suppositories with Fatty Acids Vs. TAG Oil

Five healthy volunteers participated in this study. On day one theyadministered rectally one suppository containing 10% omega enrichedfish-liver oil and 30% omega enriched fatty acid mixture (see Table 2and Example 2) and on day seven they administered identical suppositorycontaining only the fish-liver oil (40%) but no free fatty acids. Thesuppositories containing the fish-liver oil and the fatty acid mixturestimulated bowel movement causing defecation in all participants whilesuppositories containing only the fish-liver oil did not.

Example 6 Tablets with Fatty Acid and Cyclodextrin

Dry powder containing free fatty acids were prepared by weighing 10grams γ-cyclodextrin, 3 grams carboxymethylcellulose sodium (molecularweight 90,000 Da) and 0.02 grams benzalkonium chloride in a beaker glassand add pure water ad 90 ml. Then 9 grams of cod-liver oil and 1 gram offree fatty acid mixture (Example 1) was added to this solution. Afterthorough mixing the emulsion formed was lyophilized to form dry complexpowder. Then 98.5 grams of the complex powder was mixed with 0.5 gramsof silicon dioxide and 1 gram of magnesium stearate, and tablets(diameter 15 mm, weight 0.75 grams) prepared by direct compression.

Example 7 Dry Powder with Fatty Acids and Cyclodextrin

γ-cyclodextrin (gamma-cyclodextrin; 15 grams) was dissolved in 85 ml ofwater and 15 grams of the fatty acid mixture (Example 1) added to thesolution (pH 7.4). After thorough mixing the emulsion formed waslyophilized to form dry complex powder.

Example 8 Virucidal Activity of Fatty Acid Extract and FattyAcid-Cyclodextrin Complex

Monolayers of CV-1 cells (African green monkey kidney cell line) in96-well cell culture plates (Nunc, Denmark) were use to determine virusinfectivity titers. The cell culture medium was Eagle's minimumessential medium (MEM) with 10% fetal bovine serum (FBS) and themaintenance medium (MM) was MEM with 2% FBS. The fatty acid extract fromcod-liver oil, fatty acid extract (Example 1) or fatty acidextract/γ-cyclodextrin complex (Example 7) was dissolved in MM to thedesired concentration (0.5% and 1.0%) by vortexing for one min. Theextract dilutions in MM were mixed with stock solution of herpes simplexvirus type 1 (HSV-1) in ratio 4:1 and incubated at room temperature for10 min. The viral infectivity in the mixtures was then immediatelytitrated by inoculation of 10-fold dilutions in MM into wells with CV-1monolayers, 100 μL per well and four wells per dilution. The cellculture plates were incubated for 5 days at 37° C. and 5% CO₂ in air.Virus infectivity titers were then read and expressed as log_(in) CCID₅₀(50% cell culture infective dose) per 100 μL. The titers in mixtureswith fatty acid extract were subtracted from the titer of the controlmixture in which HSV-1 was diluted 4:1 in MM. The difference, i.e.reduction of titer, was used as a measure of antiviral activity (seeTable 5).

TABLE 4 The antiviral activity. Compound Virus titer Log₁₀ Virucidalactivity Fatty acid extract in a ≦1.5 >5.0 γ-cyclodextrin complexCod-liver oil (undiluted) 0 0 Fatty acid extract (undiluted) ≦1.5 >5.0HSV-1 control 6.57 ± 0.10 X

REFERENCES

-   J. J. Kabara, Fatty acids and derivatives as antimicrobial agents.    In: The pharmacological effect of lipids. Edited by J. J. Kabara.    The American Oil Chemists Society, St. Louis, Mo., 1978, pp. 1-13.-   S. Khulushi, H. A. Ahmed, P. Patel, M. A. Mendall, T. C. Northfield,    The effect of unsaturated fatty acids on Helicobacter pylori in    vitro, J. Med. Microbiol., 42, 276-282, 1995.-   N. M. Carballeira, New advances in fatty acids as antimalarial,    antimycobacterial and antifungal agents, Prog. Lipid Res., 47,    50-61, 2008).-   H. Thormar, H. Hilmarsson, The role of microbicidal lipids in host    defense against pathogens and their potential as therapeutic agents,    Chem. Phys. Lip., 150, 1-11, 2007.-   C. Vieira, S. Evangelista, R. Crillo, A. Lippi, C. A. Maggi and S.    Manzini, Effect of ricinoleic acid in acute and subcronic    experimental models of inflammation, Med. Inflammation, 9, 223-228,    2000.-   G. A. Burdock, I. G. Carabin and J. C. Griffiths, Toxicology and    pharmacology of sodium ricinoleate, Food Chem. Tox., 44, 1689-1698,    2006.-   B. E. Lacy and L. C. Levy, Lubiprostone: a novel treatment for    chronic constipation, Clin. Interv. Aging, 3, 357-364, 2008.-   Osman, F., Ashour A. E., Gad, A. M., Monoglycerides: I. Synthesis by    Direct Esterification of Fatty Acids and Glycerol, Fette, Seifen,    Anstrichmittel, 70, 331-333, 2006.-   Halldorsson, B. Kristinsson and G. G. Haraldsson. Lipase selectivity    toward fatty Acids Commonly Found in Fish Oil. Eur. J. Lipid Sci.    Tech. 106, 79-87, 2004.

1. A pharmaceutical dosage form in the form of a suppository foradministration to rectum for inducing defecation, said dosage formcomprising as an active ingredient one or more fatty acids in the formof free fatty acids.
 2. The pharmaceutical dosage form of claim 1,wherein said one or more fatty acids comprise one or more saturated orunsaturated fatty acid with a carbon chain length in the range of C4 toC36.
 3. The pharmaceutical dosage form of claim 1, wherein said one ormore fatty acids comprise a mixture of fatty acids comprising at leastabout 20 wt % of unsaturated fatty acids and thereof at least about 5 wt% polyunsaturated fatty acids.
 4. The pharmaceutical dosage form ofclaim 3, wherein said mixture of fatty acids comprises fatty acidsderived from vegetable oil selected from the group consisting ofsafflower oil, corn oil, almond oil, sesame oil, soybean oil, linseedoil, rapeseed oil, grape seed oil, sunflower oil, wheat germ oil, hempoil, and any mixtures thereof.
 5. The pharmaceutical dosage form ofclaim 3, wherein said mixture of fatty acids comprises fatty acidsderived from marine organisms.
 6. The pharmaceutical dosage form ofclaim 5, wherein said mixture of fatty acids is derived from marineorganism material selected from the group consisting of marine animaloil derived from an animal source selected from fish liver oil includingcod liver oil, tuna oil; fish flesh or fish meal including flesh or mealfrom herring, capelin, mackerel, menhaden, sardine, anchovy, horsemackerel, blue whiting, and tuna; planktonic organisms, squid andmolluscs, and any mixture thereof.
 7. The pharmaceutical dosage form ofclaim 1, comprising in the range of 50-2000 mg of said fatty acids. 8.The pharmaceutical dosage form of claim 1, comprising in the range ofabout 5 wt % to 75 wt % of said fatty acids.
 9. The pharmaceuticaldosage form of claim 1, which comprises in the range of 10-50 wt % ofsaid fatty acids and further comprises in the range of 5-25 wt %triacylglyceride oil.
 10. The pharmaceutical dosage form of claim 1,further comprising cyclodextrin.
 11. A method of stimulating and/orinitiating the process of defecation comprising administering to therectum and/or intestines one or more fatty acid in a suppository inorder to stimulate the polymodal nocireceptors in the rectal mucosa. 12.The method of claim 11, wherein said one or more fatty acid fatty acidsis in the form selected from free fatty acid, fatty acid ethyl ester andfatty acid monoglyceride.
 13. The method of claim 11, comprisingadministering in the range of 50-2000 mg fatty acids.
 14. The method ofclaim 11, wherein said one or more fatty acid comprises a mixture offatty acids comprising at least about 20 wt % of unsaturated fatty acidsand thereof at least about 5 wt % polyunsaturated fatty acids.
 15. Themethod of claim 11, wherein said one or more fatty acid is derived frommarine organism material selected from the group consisting of marineanimal oil derived from an animal source selected from fish liver oilincluding cod liver oil, tuna oil; fish flesh or fish meal includingflesh or meal from herring, capelin, mackerel, menhaden, sardine,anchovy, horse mackerel, blue whiting, and tuna; planktonic organisms,squid and molluscs.
 16. The method of claim 11, wherein said suppositorycomprises in the range of about 5-25 wt % triacylglyceride oil.
 17. Amethod of treatment selected from stimulating and/or initiating bowelmovements, treatment of hemorrhoids, bacterial infections, viralinfections including herpes simplex virus infections, and inflammations,treatment of fissura ani and pruritus ani, comprising administering tothe rectum fatty acids in the form selected from free fatty acids, fattyacid monoglycerides, and fatty acid ethyl esters, as active ingredientin a dosage form selected from a suppository, ointment, cream, lotion,paste and a formulation for enema delivery.
 18. The method of claim 17,wherein said dosage form comprises in the range of 50-2000 mg of saidfatty acids.
 19. The method of claim 17, wherein said fatty acidscomprise a fatty acid mixture derived from fish.
 20. The method of claim17, wherein said fatty acid is in the form of free fatty acids.
 21. Themethod of claim 17, wherein said dosage form further comprises in therange of 5-25 wt % of triacylglyceride oil.
 22. A pharmaceutical dosageform, comprising in the range of about 5 to 75 wt % of one or more fattyacids as active ingredient, said fatty acid formulated in a complex withcyclo dextrin.
 23. The pharmaceutical dosage form of claim 22, whereinsaid fatty acids are in the form of free fatty acids.
 24. Thepharmaceutical dosage form of claim 22, wherein said cyclodextrin isselected from the group consisting of alfa-cyclodextrin,beta-cyclodextrin, and gamma cyclo dextrin.
 25. The pharmaceuticaldosage form of claim 22, wherein the fatty acids and cyclodextrin areprovide in powder form.
 26. The pharmaceutical dosage form of claim 22,in a form selected from the group consisting of a tablet and a capsule.